We will repeat our study of the pre-eruptive influences of a zinc deficiency of subsequent dental caries susceptibility. After delivery, female rats and their suckling pups will be divided into four groups. A zinc deficient group will be fed a diet containing a maintenance level of zinc. The zinc sufficient group will receive a diet high in zinc. The pair fed group will be fed an amount of the zinc sufficient diet equal in amount to the intake of the zinc deficient group. A supplemented group will be fed the zinc deficient diet plus a supplement of zinc to maintain weights and plasma zinc levels similar to the zinc sufficient group. At weaning, the pups will be fed a cariogenic diet and after 5-6 weeks scored for dental caries. Then we will continue with studies to determine why the zinc deficiency is influencing caries susceptibility. We will examine the microflora changes with diet, eruption time of the molars, tooth histology and saliva composition alterations. Also, we will examine post-eruptive influences of zinc deficiency. Rats will be fed a zinc deficient cariogenic diet beginning at weaning and then scored for caries. This group will be compared with ad libitum and pair fed groups receiving the cariogenic diet with adequate zinc.